This invention relates to a knife assembly for a carding machine, cleaning machine or the like for treating cotton fibers and is of the type which has at least one separating knife associated with a roller or cylinder of the machine. The separating knife has a knife edge oriented against the direction of rotation of the roller and the separating knife is adjustable towards and away from the periphery of the roller.
In cards or cleaning machines the separating knives serve for removing dust, waste or trash from useful fibers adhering to the clothing of the fiber-treating roller. In cleaners the separating knives are used in conjunction with sawtooth rollers, while in carding machines the separating knives are used at the licker-in, the main carding cylinder or in cooperation with suction hoods or suction tubes. The section hoods have the purpose to carry away, in an air stream, trash, short fiber and dust particles separated by the knife. Conventionally, the knives are adjusted before operation, that is, the location of the knife, the distance of the knife edge from the roller (cylinder) and the angular position of the separating flank of the knife to the tangent of the roller are constant during the operation of the machine. This arrangement is disadvantageous in that changing the positional parameters is often difficult and therefore can be carried out only while the machine is at a standstill. The distance of the knife edge (tip) to the sawtooth clothing of the roller, for example, the licker-in may be between 0.2 to 0.6 mm dependent upon the fiber material to be processed. The setting of the distance is conventionally carried out manually with the aid of a spacer gauge while the machine is at a standstill. A readjustment of the knife is often desirable in order to adapt it to various materials, particularly to materials which have different dirt contents or dirt types.